This invention relates generally to printing on plain paper and more particularly, but not by way of limitation, to an apparatus and method for transferring an image on dielectric paper to plain paper.
In xerography and related processes, an image is electrically charged on a photoreceptor. The image is developed by a toner. The toned image is transferred from the photo-receptor onto conventional plain paper. The toned image on the plain paper is then dried. The residual toner on the photoreceptor is cleaned, and the image discharged before the cycle is repeated.
In one type of electrostatic printing, a series of electrodes are electrically pulsed. The electrodes discharge ions which form an electrically charged latent image on a dielectric paper. The image on the medium is a mirror image of the surface of the electrode. The image may be in the form of a print character or a series of images may be combined to form a print character. The charged latent images on the dielectric paper are toned in a conventional manner and then dried. In this type of printing, dielectric paper is used rather than plain paper because plain paper does not retain the charged latent image well enough to permit adequate developing by the toner. Because a special paper is required, the costs of the paper may be higher than the costs of plain paper.
Another method of electrostatic printing does use plain paper. A toner mist is introduced between electrodes discharging an ion flow and a plain paper medium. The ion flow, which is controlled by a selectively-energized aperture board, impinge on the toner mist particles. A toned image is formed on the plain paper and then dried. This system has the problem of properly controlling the ion flow through the aperture board. Also, there is a problem of controlling the particle size of the toner mist and cleaning the excess toner which may clog the apertures.